Roller bit



NOV. 7, 1933. w cHlLDS 1,933,892

ROLLER B I T Filed May 15, 1931 fl/zg. 6/4/04? gmwtoz Patented Nov. 7, 1933 UNITED STATES,

f some arr William ll. Childs, Houston, Tex, assignor to Reed Roller Bit Company, Houston, Tex, a

corporation of Texas Application May 15, 1931. Serial No. 537,530

3 Claims.

This invention relates generally to deep well drilling apparatus and specifically to roller bits. The conventional cross roller cutter rock bit, includes a pin transversely mounted in a head 3 and having a plurality of roller cutters thereon. When the bit is rotated, centrifugal force and the formation encountered cause outward movement on the pin of the innermost of these outters. The consequent crowding of the cutters renders the bit less eflicient.

This invention has for its specific objectthe provision of a roller bit embodying new and improved means to prevent such crowding of .the cutters.

The preferred embodiment of the invention is illustrated by the accompanying drawing, of which Fig. l is a partly sectional side elevation of the bit; Fig. 2, a bottom plan view partly in section; and Fig. 3, a fragmentary sectional elevation.

In the drawing, the bit head is indicated at l; the cross roller cutters at 2, 3, 4 and 5; and the side roller cutters at 6 and '7.

The cross roller cutters are mounted on a pin 8 which is secured in the head 1 by end bolts 9 and 10 and by central bolt 11. The central bolt includes upwardly and outwardly extending spindles 11a for the side roller cutters 6. and '1; and a bridge portion 11b. 2

The pin 8 is provided with annular grooves in which are bearing rollers 12 for the cutters. The

end bolts 9 and 10 extend through openings in the ends of the pin 8' and may readily be removed therefrom; and the bolt 11 has an opening 11c in which the pin 8 is removably disposed.

To prevent outward movement on the pin 8 of the innermost roller cutters 3 and 4, the pin 8 has an integral annular flange or washer 13 and a removable washer 14, the latter of which is held in place by the set screw 15. The washers 13 and 14 have heretofore been made laterally slidable on the pin 8, and this has permitted crowding of the cutters, as above set forth. In the preferred embodiment of the present invention, the cutters 3 and 4 are positively held against outward movement on the pin 8 by the washers 13 and 14. The

washers l3 and 14 also hold the bearing rollers 12 in place, and serve to prevent inward movement on the pin 8 of the outermost cutters 2 and 5.

I claim:

l. A roller bit having a head, said head having 60 three bolt openings therein; a pin; holdlng bolts extending removably through and secured to said pin substantially at its ends and removably se cured in two of said openings; a centrally positioned holding bolt having a bore through which 5 said pin removably extends; said centrally positioned bolt being removably secured in the other of said openings; a pair of cutters on said pin on each side of said centrally positioned bolt; a washer integral with said pin and between the cutters of one pair of said cutters; and a washer removablyflxed on said pin between the others of said cutters. Y

2. A roller cutter assembly including a pin; end holding bolts secured to said pin at the outer end 7 portions thereof; a central holding bolt centrally positioned on said pin'for supporting said pin at its central portion; a; pair of roller cutters on said. pin on each side of said central bolt; a washer between the cutters oi each pair of said cutters and fixed against lateral movement on said pin; and bearing rollers between each 01 said cutters and said pin.

3. A roller bit having a head; said head having three bolt openings therein; a pin; end holding bolts extending removably through and secured to said pin and removably secured in two of said openings; 9. central holding bolt centrally positioned on said pin and having a bore through which said pin removably extends, said pin being thereby supported at its central portion; said central bolt being removably secured in the other of said openings; a pair of cutters on said pin on each side of said central bolt; a washer integral with said pin and between the cutters of one pair 9 of said cutters; a washer removably fixed on said pin between the others of said cutters; and bearing rollers between each of said cutters and said p WILLIAM L. CHE-D8. 109 

